How deep to make dirt mounds for flowers?

I want to plant some flowers (snapdragons, forget-me-nots and pansies) in a mound of dirt beside our house and was wondering how deep I need to make the mound? Kristina from Rainier, WA. Thanks!

Submitted by slopitchdiva

Raised bed or mounds for growing annual flowers should be at least 6 inches deep. Deeper is better. However, you can also till the soil below the mound that you make so that roots will grow down into the existing soil.

Answered by DSchrock